Model of permanent magnet synchronous generator operating with power electronic unit

A deep knowledge of the phenomena in permanent magnet (PM) synchronous generator is necessary to predict precisely machine properties, as well as to recognize the machine condition during operation. To predict Fourier components in the stator phase current and torque, it is necessary to have dedicated mathematical models of PM generator. In the paper the modeling of synchronous machines with PM located on the surface of the rotor operating with diode rectifier is presented. The proposed method gives the possibility to omit tedious analysis of the commutation process. As a result of this a synchronous PM generator with a diode rectifier is described by a differential equation with periodically changing parameters. This allows to compute the current Fourier spectra by the harmonics balance method. Presented methodical aspects of modeling PM machines with rectifier can be useful for diagnostic purposes